Resideo - Honeywell Home AT140A1042 Universal Mount Transformer

The AT140A1042 Universal Mount Transformer from Resideo (Honeywell Home) delivers reliable 24V AC power for modern heating and cooling control systems. With a 208/240V AC primary input, 24V AC secondary, 60 Hz operation, and a 40 VA rating, it’s built for dependable thermostat control in residential and commercial HVAC setups.

Designed for universal mounting with a sturdy mounting plate, foot, and knockouts, this thermostat transformer fits a variety of control boards and enclosures. UL and CSA approvals ensure industry-leading safety and compatibility with many HVAC components.

• Primary voltage: 208/240 VAC
• Secondary voltage: 24 VAC
• Frequency: 60 Hz
• Power rating: 40 VA
• Temperature rise: -20 to 105°F
• Mounting: Plate, Foot, Knockout
• Application: Heating/Cooling Control System
• Approvals: UL, CSA

Choose the AT140A1042 for a compact, durable power source that preserves control accuracy across temperature ranges and supports reliable operation of thermostats, control boards, and other HVAC components.